Easily soluble salts of acylaminophenol-arsonic acids



Patented Feb. 9, 1937 EASILY SOLUBLE SALTS F ACYLAMINO- PHENOL-ARSONIGAGIDS Louis Benda, Frankfort-on-the-Main, and Otto Sievers, Hohe Tanne,near Hanau-on-the- Main, Germany, assignors to Winthrop ChemicalCompany, Inc., New York, N. Y., a corporation of New York No Drawing.Application September 18, 1931, Serial No. 563,664. In Germany October1,

Claims. (01. 260-14) This invention relates to easily soluble saltsespecially double alkali salts of acylamino-phenol-arsonic acids.

U. S. application Ser. No. 394,748 filed September 23, 1929, describesthe manufacture of easily soluble di-sodium salts ofacylamino-phenolarsonic acids and their derivatives and of solutionscontaining the same by dissolving in double the equivalent amount of anaqueous caustic with sodium hydroxide, products are obtained which areidentical with those of U. S. applicasodium. In order to isolate thedi-alkali metal salt the solution obtained may be precipitated by anagent which is soluble in'.water but does not dissolve the di-alkalimetal salt, such as alcohol,

19 soda or sodium carbonate solution a 4-hydroxyacetone or common saltsolution.

3-acylamino-aryl-arsonic acid. In order to further illustrate ourinvention, the

We haveinow found that not only disodium following examples are given.We wish it,.howsalts-qas disclosed in the application above reever, tobe understood that we are not limited to ferred to but dialkali metalsalts in general are the particular products nor reaction conditionsdistinguished by a high solubility and at the same mentioned therein.Jtgaeedby the absence of any irritation when in- Example 1 (sodiumlithium salt) Like the disodium salts they are found to show 165 gramsof pure 3-acetylamino-4-hydroxyno toxicity which is a surprising factsince the benzene-l-arsonic acid are introduced into 600 cc. lithium andpotassium salts of 3-acylamino-4- of hot' water and dissolved by theaddition of phenol-l-arsonic acids hitherto described (see 60 cc. of 10N-caustic soda solution and 120 cc.

U. S. specification No. 1,532,361) are unsuitable of a 5 N-solution oflithium hydroxide The sofor therapeutical purposes because of theirlution is heated for some time with animal chartoxicity; coal, filteredand. made up to 1000 cc. The steri- V "The new dialkali-metal saltscorrespond. to lized solution may be used as such for injecting Lo theprobable general formula: purposes or it may be diluted. It exhibits there- W 1 markable property of maintaining dissolved coni ,As03 Hsiderable amounts of mono-sodium salt. These mixtures are also suitablefor therapeutical purposes. z By treating the same arsonic acid with 240cc. X- NHacy of a 5 N-solution of lithium hydroxide without I the use ofcaustic soda, the corresponding di- 0 lithium salt is obtained which ismore easily (wherein X stands for hydrogen or chlorine, Y Soluble uShows Otherwise Similar P p tiessodium or potassium and Z for potassiumor am 2 (Sodium pottassmm salt) 1 mm According to one feature of thisinvention, the 1552 grams of p ety1am -0 O 04- process of manufacture iscarried out in the same hydroxy-benzene-l-arsonic acid are ssolved inmanner as. described in the application above 1000 P Of watehwhile d 50000- Of a 10 N- referred to, by dissolving the acids concerned i causticsoda solution and 500 cc. of a 10 N-caustlc aqueous solutions of doublethe equivalent quanpotash solution. The clear solution is allowed titlesof alkalies of which only one equivalent may to run. While Wellstirring, into 5000 cc. of cooled be caustic soda or sodium carbonate.pur al h l. w r up the s u -p assium According to a further feature ofthis invensalt separates in a crystalline form. It is filtered tion thedialkali metal salts of these acids may be by suction and washed withalcohol and ether. obtained by another process starting from amono-alkali metal salt instead of the free arsonic Example (Potassiummhwm salt) acid and treating this salt with one molecular 1375 grams ofpure 3-acetylamino-4-hydroxyproportion of an alkali metal hydroxide. BybenZene-l-arsonic acid are dissolved in 1000 cc.

using in this case a hydroxide of an alkali metal different from thatpresent in the mono-alkali metal salt of the arsonic acid, dialkalimetal salts are obtained containing two difierent atoms of alkalimetals; by treating a mono-sodium salt of a 5 N-solution of lithiumhydroxide and 500 cc. of a 10 N-caustic potash solution and 1000 cc. ofwater. The clear solution is allowed to run slowly into 10 liters ofcooled pure alcohol whereupon the potassium lithium salt separates inthe form of fine crystals. It is filtered by suction and washed withalcohol and ether.

Example 4.--(Soaliam potassium salt) 185 grams of the mono sodium saltof 3- acetylamino 4 hYdI'OXY-bGliZEIIG-1-31SOI1i0 acid (containing fourmolecules of water of crystallization) are mixed with cc. of water, and50 cc. of a 10 N-caustic potash solution are added, While shaking. Theclear solution is filtered into 1500 cc. of pure alcohol and the sodiumpotassium salt precipitated is filtered by suction and washed withalcohol and ether. It forms a White crystalline powder which is readilysoluble in water.

By starting from the mono potassium salt and treating it with potashsolution, the corresponding di-potassium salt is obtained, which showssimilar properties.

Example 5.-(Di-s0dium salt) 169 grams of3-benzoylamino-4-hydroxy-benzene-l-arsonic acid are introduced into 1000cc. of hot water and dissolved by the addition of 50 cc. of a 10N-caustic soda solution. After cooling the mono sodium salt is isolatedby filtration. It is dissolved in 200 cc. of water and 50 cc. of a 10N-caustic soda solution and filtered into 1500 cc. of pure alcohol.After filtering, washing and drying the product forms a whitecrystalline powder, easily soluble in water.

Example 6.--(Potassiam lithium salt) wherein X stands for a member ofthe group consisting of hydrogen and chlorine, Y for a member of thegroup consisting of sodium and potassium, Z for a member of the groupconsisting of potassium and lithium, and R for a member of the groupconsisting of acetyl and benzoyl, which products are crystallinecompounds soluble in threefold their weight of water, very difficultlysoluble in strong alcohol and acetone and insoluble in ether,

2. The di-alkali-metal salts of hydroxy-acylamino-aryl-arsonic acids ofthe general formula:

which product is a crystalline compound soluble in threefold its weightof water, very diificultly soluble in strong alcohol and acetone andinsoluble in ether.

4. The sodium-lithium salt of 4-hydroxy-5-chloro-3-acetylamino-benzene-l-arsonic acid of the formula:

AsOs

which product is a crystalline compound soluble in threefold its weightof water, very difliculty soluble in strong alcohol and acetone andinsoluble in ether.

5. The potassium-lithium salt of 4-hydroxy-3-benzoylamino-benzene-l-arsonic acid of the formula:

which product is a crystalline compound soluble in threefold its weightof water, very difiicultly soluble in strong alcohol and acetone andinsoluble in ether.

LOUIS BENDA. OTTO SIEVERS.

